Reply to Thread

Message:: [QUOTE="John the Jute, post: 595036, member: 17740"]IIRC, the change was in 1959. It was not a change that created a metric ounce. As you say, that doesn't exist. It was change that recognized that each country had a different troy ounce. Each country had a hunk of metal that represented a troy pound, which had been copied, as accurately as technology permitted at the time, from some other country's troy pound. Mid-20th-century technology, which was accurate to microgrammes, showed them all to be very slightly different. Most countries agreed to piggyback on the work that was being done to define the kilogramme precisely, and to redefine their troy ounce as 31.1034768 grammes. This made no significant difference to precious metals trading (at the time, a microgramme of gold cost about a nine-thousandth of a cent) and saved arguments. This means that 20g is closer to 0.643015 troy ounces. <img src="styles/default/xenforo/clear.png" class="mceSmilieSprite mceSmilie8" alt=":D" unselectable="on" unselectable="on" /> Later, John[/QUOTE]